中文摘要：

提出了慢度和偏振的摄动完全是由平面波非均匀性参数D引起的观点，改进了Cerveny和Psencik提出的计算各向异性弱粘弹性介质中非均匀平面波慢度和偏振的摄动公式，给出了在形式上更为简单的摄动公式。与原有的公式相比，新的摄动公式对均匀平面玻是精确的，并且在形式上更加简洁。对一个二维横向各向同性弱粘弹性介质模型，根据新的摄动公式与原有的摄动公式及精确公式，用数值方法分别模拟了平面波（qP，qSV，qSH）沿传播向量方向的慢度虚部Im（σ）和质点振动。比较发现，用新的摄动公式得到的qP和qSV波的慢度虚部Im（σ）和质点振动比原有的摄动公式更精确，而对qSH波两种方法近似效果相差无几。经过综合比较，可以断定新的公式要优于原有的公式。

英文摘要：

After proposing a viewpoint that the perturbation of slowness and polarization is fully due to the inhomogeneous parameter D of inhomogeneous plane wave, the authors have improved the original perturbation formulas used by Cerveny and Psencik for the slowness and polarization of the inhomogeneous plane wave propagating in anisotropic weakly viscoelastic media, with new perturbation formulae for slowness and polarization, which are more concise than the previous and are exact for homogeneous wave. Numerical modeling for imaginary part of slowness Im（σ） and particle motion shows that the new perturbation formulae are better than the original ones for qP and qSV wave and have almost the same accuracy as the original for qSH wave.